I understand that weight is a key factor when choosing a sports wheel. It’s probably the first thing most people think about. Yet what many may tend to overlook is the importance of a wheel’s rigidity or stiffness.

A recent article in Option Magazine attempted to compare the function of “rigidity” or “stiffness” of a wheel versus its “lightweightedness” and how these 2 factors affected overall performance. Enkei and GT-R tuner MCR together conducted a test using a highly rigid wheel, the GTC 01 and a specially-made, lightened version of the same wheel.

The test was meant to prove that although most people understand the merit of seeking a lightweight performance wheel, most tend to think that as long as a wheel is rigid or strong enough not to crack or bend, it should be fine. What they point out in this article is that when producing a true, race worthy wheel, reputable manufacturers take into account the degree of rigidity depending on the specifications of the particular racecar. The weight factor is taken into consideration only after the rigidy factor.

If you’re interested in reading this article, Jin took the liberty to translate the full article into english. Here’s a summary of the tests and results:

Regular High Rigidity Enkei GTC-01 18×10 +22: 23.76 lbs.
Specially Lightened Version Enkei GTC-01 18×10 +22: 19.8 lbs.

The weight of the lightened version was reduced by 3.96 lbs. Both used Advan A048 (265/35-18 M-Compound). Testing was performed at Ebisu East Circuit using MCR’s Z33 driven by Kobayashi and under the same specs (ie., tire pressure, # of laps, etc.)

Regular High Rigidity GTC-01
Best Lap: 1 min. 4.646 seconds
Top Speed: 147.16 km/h @ 17.83 seconds

Specially Lightened GTC-01
Best Lap: 1 min. 5.045 seconds
Top Speed: 141.46 km/h @ 17.74 seconds

A very rough and quick recap: The surface temperature of the tires for the less rigid, specially lightened GTC-01 were higher overall with extensive wear on the outer portion while not enough contact/usage on the inner portion. The high rigidity regular version GTC-01 showed even usage throughout the inner and outer parts of the tire. Also, the low rigidity, lightweight version wheels gave/bent when taking aggressive high speed turns even affecting the height of the car which even led to scraping and alignment problems. Furthermore, the lighter version accelerated much quicker, but ultimately did not lead to faster times. In summary, Kobayashi expressed that a balanced wheel with both rigidity and lightweight characteristics is important, but he never imagined that the effects of rigidity played such a large role.

E-mail kent[at]ame-wheels.com or here at kent[at]og-made.com with header “Option Article Request” and I’ll kindly e-mail you a .PDF file of the translated article. This will also be posted on the AME website in the near future.

There are still people out there that’ll ask strange questions like, “Why do the 17″ Advans produced by Enkei cost $400 more than a 20″ chrome Enkei wheel?” Because one is produced from Enkei Japan and the other is stateside Enkei’s way of cashing in. I ain’t hatin’. Here’s a list of some of the products that Enkei Japan produces for others..in Japan.

1) Yokohama Advan Series
2) Yokohama Tire AVS Series
3) OZ Superturismo GT-EVO
4) Lorinser (Lorinser S-Class w/ Lorinser RSK 6 pictured first above)
5) AC Schnitzer (AC Schnitzer GP 3.10 w/ AC Schnitzer Racing Type VI pictured second above)
6) Takechi Project Hart Series
7) G-Corporation High-End Series (2PC., 3PC.)
8) Crimson Racing Sparco NS06 Cheetah (no association to Sparco Italy)
9) Lineasport (Crimson Co., Ltd.)
10) Myrtle Louis (Crimson Co., Ltd.)
11) Fabolous Genesis
12) Motorsports IRS
13) easyRiders TMW
14) easyRiders Tecnocast

This is for the style-conscious wheel connossieurs that prefer that high-quality, multi-piece wheel. Especially those with generously polished lips. You have to clean your wheels often and your environment will usually constitute how often. With AME wheels, specifically, they all have a clear coat over the entire wheel to protect the metal. However, by not protecting the clear coat, chemicals can eat through it and ultimately damage the metal surface causing undesirable staining, blotchiness or fogging to occur. This usually occurs from a substance that is either too alkaline or too acidic and can range from using astringent wheel cleaners, liquid chemicals used in sprinkler systems, foreign substances that splash during driving and even rain in some cases, but not limited to. When cleaning, always clean and dry with a non-abrasive soft cloth and rinse when cool with clean water. If using a wheel cleaner, be very careful in choosing one that isn’t too acidic. Dish washing soap generally isn’t bad since it’s not too harsh and intended to come in contact with your hands. AME performs litmus pH tests on claims that come from customers and the majority of the time it’s evident that a foreign substance either too alkaline or too acidic has come into contact with the surface for too long. Japanese wheels are like girls. They’re sensitive and you have to take care of them. Take care of them and they’ll take care of you.

Although the MAT process is a primary element of the complete Enkei wheel making process, explaining the total wheel-forming process and the objectives for each step will produce a much more clear picture.

The MAT process is only applied to produce the rim/barrel portion of the wheel. This is significant because up to 80% of the stress occurs towards the outermost portion of the barrel. (Imagine a plastic cup. The bottom of the cup represents the face of a wheel. The top of the cup represents the outermost portion of the barrel. Now put the cup on its side and imagine where most of the tension would occur.) MAT essentially is an Enkei proprietary method of Flow Forming, but on a different level and currently performed only in Hamamatsu (for the aftermarket sector). Most manufacturers using the flow-forming (aka spun-forged, rim-rolling) method utilize a Low Pressure (LP) type of casting combined with the flow-forming process. Enkei’s MAT process differs in that 1) It utilizes an improved, Enkei proprietary method of Gravity Die Casting (GDC) (which has been coined GDC+MAP) combined with 2) the MAT flow-forming process that undergoes a series of precision constructive phases that improve the mechanical properties of the material. Standard flow-forming does not effectively alter the molecular micro structure.

Why Gravity Die Cast (GDC) instead of Low Pressure (LP) Cast?
Low Pressure casting injects aluminum into the mold from the face first and fills up the remaining rim/barrel portion of the wheel afterwards. This allows the face of the wheel to become strong by hardening first. However, it does not allow the rim/barrel portion of the wheel (the most crucial area) to be as strong because it has less time to harden. Hence, the most important area of the wheel is weaker.

In contrast, Gravity Die Cast allows for aluminum to be poured in from the rim/barrel portion of the wheel slowly filling it up and hardening first, ultimately creating a strong rim/barrel.

What is Gravity Die Cast (GDC) + MAP?
It is Enkei’s proprietary version of the standard GDC process combined with other processes dubbed MAP. First of all, Enkei uses A357 aluminum ingots combined with a special blended material to further increase the strength and life of the aluminum. Before being poured into the mold, the temperature is increased to xxx degrees. When pouring, Enkei uses a tilt method with precise angle and consistent rotation to decrease air bubble formation and increase overall balance. After the pouring, temperatures is decreased to xxx degrees for cooling. However, this occurs much quicker than standard casting processes allowing for a more balanced material content. Specific positioning and releasing of “pin mechanisms” enable this advanced cooling technology. Imagine sugar water and how the content between the top and bottom can easily differ. Basically, the quicker the better. The temperature is then increased back up to xxx degrees and then quickly dropped to xx degrees for the final cool off process. This helps to evenly spread out the silicone content throughout the material.

The levels of speed and the automated time and temperature management processes are highly advanced.

Finally, the MAT process is employed. A portion of the rim/barrel is cut off leaving behind only stubs. These stubs then forego the MAT process improving the micro structure of the aluminum creating a “Metal Flow” resulting in a stronger and more rigid rim/barrel. Imagine that this “Metal Flow” represents the material with a web/thread/weave-like linear flow creating an environment difficult for an impact to fracture, tear, split or sever the material. The complex GDC+MAP combined with the MAT process helps improve the wheel structure greatly. This is why AME specifically chose Enkei to produce the new TM-02 wheel debuting soon.

A good question to begin with. You can learn alot by taking the time to read so please do so and click here. In a nutshell, wheels can actually expand and contract up to 10% of its original diameter under extreme conditions (such as in F1). A true quality wheel will enable this “flexing” to occur precisely. Poor quality wheels either aren’t able to achieve this or do not achieve it in an efficient, desired manner. A hard, callous wheel is not desirable as it does little to absorb nor relieve any unnecessary stress/tension that can channel its way to the chassis and components of a vehicle leading to unwanted results in performance and comfort. A quality wheel is not only one that is strong or light, but one that has balanced strength and weight characteristics that help to ease this flex/tension properly. This is the goal of MAT. This MAT wheel forming process is unique and considered to be of the highest technology improving the material properties of the wheel and its overall performance characteristics. MAT enables production of an accurate and balanced combination of weight, strength and rigidity. Too much of one characteristic doesn’t necessarily produce better results. This balance is what Enkei’s high-performance wheel production methods are centered around. (There’s a good amount of information on the Enkei North America website. It might not be the most stylish site, but it definitely matches Enkei’s engineering personality.)

While Dom’s been working on his project and slowly yet strategically planning his efforts into the racing world (where Endless truly belongs), Jin (and Julie) seem to have their hands full with the relaunch of the Endless website, amongst other things. Norio and I have been busy with most of our efforts focused on AME and its new 1 pc. wheel debuting early 2008. And since AME is produced by Enkei Japan, I figured I’d begin a series of posts dealing with Enkei’s proprietary MAT wheel forming technology. The fact of the matter is that although in Japan and worldwide, Enkei is easily recognized as the supreme wheel maker/supplier, its brand is a bit tarnished in our tiny little aftermarket segment here stateside which I believe has to do with US efforts in the past trying to adapt to the US market instead of changing it. (I’m talking about basically everything but the Racing Series line of wheels.) You can’t blame ‘em. Well, maybe you can. In anycase, let it be known that Enkei is an engineering company first and foremost. Not many can say that. And while most “wheel makers” are busy coming up with (or simply ordering) new designs, names, logos, price points, sales tactics and marketing ploys, Enkei does all of that as well of course, but it’s main focus is endlessly figuring out how to make its wheel perform better. MAT technology and its continuous advancements are what make it perform better. I’ll lightly be touching on topics such as 1) The Weight Factor, 2) Forged vs. Cast, 3) the Importance of OEM, 4) the Enkei Heritage, brands produced by Enkei, where AME plays into all of this and other related topics. I’m not sure where and when this will end, but I’ll be trying to correct the minds of some of the misinformed and miseducated when it comes to wheels while learning along the way as well. I guess you can call this an introduction of what’s to come.

For awhile I’ve been wondering, how do alot of these cheap, knock-off wheels have JWL and VIA marks? How do they get approved? It turns out, many don’t. What you see here is a fake sticker written in Japanese. When they produce the wheel, they simply incorporate the JWL and VIA logo marks into the mold and add a fake sticker to give it “legitimacy.” I believe this was a Volk knock-off. Sneaky.

Here’s a real sticker approved and received by JAWA. All companies officially registered with JAWA are given a registration number. AME’s happens to be #202. So, from now on, if you see a wheel with the JWL and VIA marks, but you sense something wrong, look for the sticker on the back. It should look just like this and have a number. Unfortunately, we’ve also seen fake copies of this sticker as well. How do we know? Someone complained about a defect and the number on the back indicated that it was an AME wheel. Turns out it wasn’t. The sticker looked real and used our JAWA registration number, but it was in fact, a fake. Super sneaky.

If I can find a listing of JAWA registered companies, I will post it.

Bridgeport air valves are made in Italy. The company has been around for a long time. Their valves are used in F1.

The Bridgeport valve can be advantageous in that it’s an all metal construction being less prone to rubber degradation and leaks. Easy to install as well.

Light, produced out of of aluminum and re-usable. Anodize to a preferred color? Why not. Aesthetic appeal!

Enkei believes that the water used in the casting, manufacturing and machining processes is crucial in ensuring high quality wheels. Enkei has a separate water filtration facility at each plant to provide a consistent water standard throughout the entire manufacturing process. Filtration helps to eliminate much of the chemicals, minerals and other impurities that may lead to physical and cosmetic quality issues. Filtration eliminates the possibility of impurities inside the water that can clog the machinery, nozzles, etc. which are extensively used in aluminum alloy wheel production. It is an enormous cost to maintain the water filtration, but nonetheless a necessity in maintaining the overall quality for Enkei wheels, which of course benefits AME as well.

ALL wheel manufacturers in Japan use only the highest grade aluminum ingots. But, along with Enkei’s superior MAT technology, we know that Enkei blends a proprietary formula of additives to increase wheel strength, flexibility and stability. Enkei is currently in their 2nd generation of rim-rolling technology (wheel companies such as Enkei and RAYS continue to increase their know-how and technology always striving for something better). The world’s largest automotive manufacturers (Toyota, Honda, Nissan, etc.) and F1 Racing teams have carefully selected Enkei wheels based upon overall quality and performance. OEM specifications are significantly more severe than testing conducted for aftermarket wheels and all AME wheels are produced under these same standards. The true value of Enkei’s rigorous internal standards is confirmed by their complete dominance in the high-end OEM wheel market.

Some specific examples that could be used is the paint quality between Enkei and other manufacturers. Although it takes a long time to get a new color approved, there are so many internal tests at Enkei that it can not be avoided.

Other manufacturing plants and especially the Chinese plants can kick out new colors every couple of weeks. This is convenient, but the wheels shouldn’t be expected to be used for more than a couple of years and also in areas with snow will cause discoloring, etc.

ALL Enkei wheel paints are tested and approved under strict OEM testing procedures which are used in all aftermarket wheel products. The significance of this is that it is much more expensive to paint wheels using OEM grade paint. Others do not do this and continue to have issues with some of their paints after a few years since they do not have the extensive OEM/Race paint background as Enkei. Some of the paints by other manufacturers have been launched quickly and end up being claims later on.

Enkei will throw out paint after a period of time even though it is still useable by anyone else’s standards. Kyoho has to argue with them since it happens with domestic market products. Each drum of paint costs about $xx,xxx.xx and makes over 10,000 wheels, but Enkei will toss it if Kyoho is not ordering within a fixed period of time.

You can learn alot about the quality of a wheel from the barrel (as well as the normally unseen inside portions which we’ll get into later). Today, let’s talk about a regular barrel vs. a reverse barrel. You might not be able to tell from the pic, but the face design of both wheels in the picture face to the left. The wheel on the left is a performance-oriented, sports wheel. This particular one has a very shallow, regular barrel. The wheel on the right is a luxury-based wheel. This particular one has a deep, reverse barrel. True sports wheels tend to use regular barrels meaning that the well of the wheel tends to be towards the face side of the wheel. Usually, this is meant for better caliper clearance. Luxury wheels tend to use reverse barrels meaning that the well of the wheel tends to be towards the back side of the wheel. Usually, this is done for aesthetic purposes to make the face design look bigger. The width and depth of the well is accurately calculated for maximized balance and strength. Regardless of the well placement, barrels without a well are for the most part, flat and tend to be thicker and heavier. The well of the barrel creates strength, similar to the thought that a piece of paper that is folded as opposed to not being folded, is stronger. So, a barrel with a well is both usually thinner and stronger while a flat barrel tends to be thicker and heavier. And of course, similarly, the barrel constitutes whether the tire should be regular-mounted or reverse-mounted. Pardon the funky pic.

The classic Split-Spoke design is considered to be one of the strongest and lightest possible wheel design. Don’t ask me why, but it’s known to be true due to its architecture and has become synonymous with Enkei. It has something to do with minimal material used while maintaining optimal strength. It also has one of the highest levels of heat dispersion from brake calipers. I think we’ll begin to see more of this design style in the future. Mark my words. The Tracer Spec-M is considered to be one of the lightest performance wheels around. Our new 1-piece lightweight racing wheel is currently in the works as well. It should be more “fashion-forward” while maintaining its strength and lightweight attributes.

SBC is a new and unique finishing technique that has recently been adopted by Enkei. While other colored wheels tend to fade from both the sun as well as prolonged periods of time, an SBC finish will withstand time and has an interesting look. Usually, SBC colors are darker such as the SBC Black shown here. The process begins with an undercoat. Then a base coat (usually a deep, darker color such as black, red, or blue). Finally a chrome/aluminum blend top coat. Notice this wheel has a dual flanged lip for added protection.

Side Note: Make sure you have enough air in your tires. As a rule of thumb, whatever your standard PSI is for your OE tire (check the label on your door well), as the wheel size increases by an inch, the PSI should increase by 10%. So if you’re running an 18″ w/ a recommended PSI of 35, your new 19″ should have a PSI of…you do the math.